On 6/24/19 7:46 PM, Damien Le Moal wrote:
To allow the SCSI subsystem scsi_execute_req() function to issue requests using large buffers that are better allocated with vmalloc() rather than kmalloc(), modify bio_map_kern() to allow passing a buffer allocated with the vmalloc() function. To do so, simply test the buffer address using is_vmalloc_addr() and use vmalloc_to_page() instead of virt_to_page() to obtain the pages of vmalloc-ed buffers.Fixes: 515ce6061312 ("scsi: sd_zbc: Fix sd_zbc_report_zones() buffer allocation") Fixes: e76239a3748c ("block: add a report_zones method") Cc: [email protected] Signed-off-by: Damien Le Moal <[email protected]> --- block/bio.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/block/bio.c b/block/bio.c index ce797d73bb43..05afcaf655f3 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1501,6 +1501,8 @@ struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len, unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT; unsigned long start = kaddr >> PAGE_SHIFT; const int nr_pages = end - start; + bool is_vmalloc = is_vmalloc_addr(data); + struct page *page; int offset, i; struct bio *bio;@@ -1518,7 +1520,11 @@ struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len,if (bytes > len) bytes = len;- if (bio_add_pc_page(q, bio, virt_to_page(data), bytes,+ if (is_vmalloc) + page = vmalloc_to_page(data); + else + page = virt_to_page(data); + if (bio_add_pc_page(q, bio, page, bytes, offset) < bytes) { /* we don't support partial mappings */ bio_put(bio);
Reviewed-by: Bart Van Assche <[email protected]>
